Lake from sulfonated azo dyes.



UNITED srrrrns Parser enrich.

EMIL WURTHNER, OF STUTTGART, GERMANY, ASSIGNOR TO THE FIRM OF G. SIEGLE & 00.,

' G. M. B. H., OF STU'lTGAR-T, GERMANY.

LAKE FROM SULFONATED AZO DYES.

Specification of Letters Patent.

Patented April 13, 1909.

Application filed. January 2, 1908. Serial No. e09,)l6.

' Stuttgart, Wilrtemberg, Germany, have invented certain new and useful Improvements in Processes for Hat-king, Dye-Lakes of Sulfonated Azo Dyes; and 1 do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

The manufacture of dye lakes of the sul fonated azo dyes has hitherto usually been done by treating the completely formed azo dye at a suitable temperature in an aqueous solution or in suspension with metallic salt solutions, substances which are insoluble in Water, such as alumina, blane-lixe and heavy-spar, lithopone, kaolin and the like being also frequently employed in suspen sion in the dye solutions. The formation of lake then takes place by the acid oi the salt of the dye stuil combining with thebuse of the metallic salt by a double decomposition, that is to say where chlorid of barium and the sodium ,salt of the dye stufi are used the baryta salt of the sulfo-acid and common salt are formed. In )lace of the dye itself, the tree dyeing aci has also been employed hitherto in an aqueous solution or in suspension. n no case however in making the lake of the sulfonated azo dyes was the start made from the components of the same, but the lake formation was [irst undertake-u after these components had been combined with one another.

Now according to the present invention it, is not at all necessary, for making the lake of the sulfonated azo dyes, to completely produce the latter before the formation of the formation of the lake then takes place di-- rectly, as is evident without further explanation, and successively in proportion as the combination progresses. The reaction ac cording to the present invention thus takes place in a totally different way than by the i action of the "finished dye on the metallic salt, because he dye is separated out as dye lake in staid nlasceml'i and in addition to the already formed. dye lake up to the end of the dye lake formation, there is always an Inn combined dye component present. It is impossible that this process should take place with the methods employed hitherto for the making of the lake and in it lies the object ofthe invention. In place of metallic salt solutions, in this improved process precisely as in the" older processes, metallic-oxids, hydroxide r warbonates may be employed.

According to the process constitutin this invention, dye lakes of the sulfonate azo dyes maybe made in a substantially simpler manner, considerably cheaper and also more uniformly than is possible with the older methods in which the lake is produced by the round-about Way of first making the dye.

lilxample: 22.3 parts beta-naphthylamin alpha-sulfo-acid are dissolved with 5.5.parts oi calcined soda and the resultant sodium salt is after filtration and the addition of 7 parts of sodium nitrite at about 10 (.3. diazotized with 38 parts oi hydrochloiic acid of Be. To the diazo compourulwhich is then obtainedin the form of a brownish paste there is added after dilution with cold water 20 nirt-s of crystalline chlorid of barium dissolver in five times its weight of water and J parts of soda lye of B. Then under constant. stirring the fluid hereinbel'ore described is added to a cold solution of 15 parts beta naphtholin 13$ parts of soda lye ol' 40 B. After the I'vaction which proceeds smoothly is ended,

the resultant lake is washed by decapitation two or three times and then heated to boiling point. It corresponds to the dye stuff lake which can be obtained with chlorid of barium from commercial lithol red ll.

All the dye lakes produced according to the foregoing process may he brought into commerce directly as concentrated dye lake,

dry or in an aqueous past-e, or even in a wet bining the mixture with the renmining comor dry condition as a mixture with suitable ponent. substances. In testimony whereof I aflix my signature,

I declare that what I claim is in presence of two witnesses. The process of making dye lakes which EMIL VWJR'JIHNER. consists in first mixing a metallic compound Witnesses: forming a lake base with one of the compo i JEAN GULDEN,

i nents of a sulfoneted azo dye and then com- 1 A. B. DRAUTZ. 

